NbN ultra-thin films for HEB-based THz systems
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Typ
Examensarbete för masterexamen
Master Thesis
Master Thesis
Program
Wireless, photonics and space engineering (MPWPS), MSc
Publicerad
2013
Författare
Krause, Sascha
Modellbyggare
Tidskriftstitel
ISSN
Volymtitel
Utgivare
Sammanfattning
The key technology for low-noise THz receivers operating above 1 THz, lies inevitably in the employment niobium nitride superconductors with critical bulk temperature of 16-17K. The enhancement of HEB’s limited IF bandwidth has been a relevant topic for two decades and is associated with the quality, hence critical temperature, Tc, of the 3.5-6nm thin NbN films. This thesis revisits the concept of employing buffer-layers which have not been utilized yet to deposit NbN onto. As a result, state-of-the-art 5.5nm thin NbN films have been successfully deposited exhibiting Tc as high as 13.2K and RRR-figure-of-merit close to unity. These films show considerable potential for highly-integrated THz electronics.
Beskrivning
Ämne/nyckelord
Grundläggande vetenskaper , Annan naturvetenskap , Annan teknik , Basic Sciences , Other Natural Sciences , Other Engineering and Technologies